Common use of Switchgear Clause in Contracts

Switchgear. Proprietary Information Page 10 AES IRONWOOD CONTRACT FINAL ISSUE - OCTOBER 30, 1998 -------------------------------------------------------------------------------- o Continuous Current: o Main Breaker: Sized to match transformer o Feeder Breakers: 800 A frame and/or 1600 A, as required o Maximum Voltage: 635 V o Insulation Level: 2.2 kV rms low frequency withstand o Interrupting Current: 65 kA symmetrical The low voltage metal-enclosed switchgear has been engineered to provide safe, reliable, and economic control and protection of low voltage distribution systems up to 600 V. The breakers are UL labeled for use in switchgear. Both the switchgear and circuit breakers are built and tested to applicable NEMA, ANSI, IEEE, UL and CSA standards. AUXILIARY TRANSFORMERS Some plant 480 V auxiliary loads, such as the water treatment MCC's and the cooling tower MCC's, may be fed directly from auxiliary transformers that step down the voltage from 6900 V to 480 V and have a kVA rating compatible with their specific loading. These auxiliary transformers will be dry-type, indoor or oil-filled, outdoor designs, as appropriate. The dry-type, indoor auxiliary transformers are similar to the SUS transformers, except that the low voltage terminations will be suitable for cable exit. The oil-filled, outdoor auxiliary transformer ratings and features are: Outdoor Auxiliary Transformers: o Voltage Ratings: o H Winding: 6900 V, 95 kV BIL, delta connected -------------------------------------------------------------------------------- Proprietary Information Page 11 AES IRONWOOD CONTRACT FINAL ISSUE - OCTOBER 30, 1998 --------------------------------------------------------------------------------